The next generation of booster is the V1.5 version. While
the V1 only boosted the CPU to 16MHz, the V1.5 also includes boosting
speed to the TOS ROMs. The new board is slightly larger than the V1 and
sees the removal of the TTL logic IC's in favor for a GAL. TTL logic alone
was unfortunately not fast enough to work with Fast-ROM so the choice
to move to a GAL was required.

In order for the ROM to work at higher speeds, the ROMs
need to be replaced with a suitable "Fast-ROM" kit which I also
sell in my store. 16MHz CPU generally adds around 25% speed boost to the
overall speed. Running Fast-ROM gives up to a additional 30% boost to
GEM/TOS related calls.

Add a blitter
to your STFM/MEGA and see the figures hit lightning speeds! See the bottom
of the page for results.

There is a pad called "SW" which can be connected
to a switch to link the wire to 0V. When SW is left disconnected / floating,
it enables 16MHz mode. When SW is connected to 0V, it forces 8MHz mode.

The above figures show in orange the speed boost over the V1 booster.
In general this gives a additional boost of 25-30%. While Blitting sees
71% speed boost over a stock machine. The statistics showing average of
143% is a little tainted by the fact some results do not see a speed boost
as the MHz speed is not increased any faster than the V1. The V1 booster
was 25-30% faster over a stock machine, and the V1.5 is 25%-30% faster
than the V1. So overall the speed increase is about 50% over a stock machine.

Fitting of the booster is very similar to the V1 with the addition of
1 extra wire.

CE line must be kept short to the booster board. The wire solders directly
onto the CE 1M pad on the motherboard as shown above. This wire connects
to the CE pin on the booster board.

Similar with the V1, the 16MHz line is taken from the shifter (pin 39)
and connected to "S39" on the booster PCB.

Similar to the V1, the orange wire connects to the clock pin on the motherboard
(or IC socket if used) which then connects to the MB pad on the booster
PCB. The CPU clock pin is bent upwards to the PCB where the booster supplies
the new CPU clock.

Above we have results using my modified version of Gembench (version
5). The first image above shows the CPU & ROM boost. The second image
shows the same CPU & ROM boost but with the addition of a blitter.

We can see the blitter really kicks things into gear giving a wooping
302% display performance!